Bill Kristol, who served in the administrations of Republican presidents Ronald Reagan and George W. Bush, says his nonprofit organization Defending Democracy Together is seeking a GOP candidate to run against [President] Trump in 2020.

“We are thinking of and doing preliminary work to prepare for a primary run against Trump,” Kristol said in an interview on Thursday. “People aren’t going to say they will run against Trump unless they have the infrastructure but I’ve been trying to persuade people that it may not be that difficult,” he added.

If a viable primary is to be mounted, it will be because: One, Trump is still there; and two, he is dragging the party down, has been shown to have engaged in illegal or impeachable action, and has continued to mentally and temperamentally deteriorate. Logically, the challenger cannot be someone who carried water for Trump — sorry, Sens. Ted Cruz (Tex.) and Tom Cotton (Ark.) — or could never manage to really stand up to him (we’re looking at you, Sen. Marco Rubio), or someone who was never really around to fight the big fights (where is Mitt Romney, by the way?)

It is less important, I would suggest, where the person stands ideologically than where the person stands on defending the rule of law, democracy and a free press. Let’s look at those mentioned as possible contenders: Sens. Ben Sasse of Nebraska and Jeff Flake of Arizona; Ohio Gov. John Kasich; Massachusetts Gov. Charlie Baker; and Maryland Gov. Larry Hogan. What have they been doing?

Hogan, Baker and Kasich opposed Trump’s efforts to repeal the Affordable Care Act with no viable alternative. They came forward with an alternative. At the time, it was very unpopular with the Republican base, but if the party takes a beating this November because it didn’t defend protection for preexisting conditions, these three will look prescient.

When it came to protecting special counsel Robert S. Mueller III, Flake voted with other Republicans to provide Mueller some protection; Sasse voted against it.

Baker and Hogan refused to send National Guard troops to assist in Trump’s vile family-separation policy.

While Flake has generally voted with Republicans in support of Trump measures, he’s voted against Trump’s extreme immigration plan (and for a compromise that Trump opposed), in favor of taking back tariff authority, against Gina Haspel’s nomination as CIA director, and in favor of sanctions against Russia.

Kasich has routinely ripped Trump in print and on television regarding trade, foreign policy, immigration and more.

Flake has given impassioned speeches in defense of the rule of law, the free press and conservative economic principles, and has called out Trump personally for his conduct. Sasse has sent out some really pointed tweets. They both warned Trump against firing Attorney General Jeff Sessions.

That said, neither Republican senator insisted on an investigation of Trump’s foreign emoluments or conflicts of interest involving the president and his family. Neither brought censure motions (e.g., after Charlottesville, for endorsing Roy Moore); voted against a problematic, key nominee (even those who later were fired or forced to resign); denounced Trump’s hiring of Stephen K. Bannon (way back when); or called for hearings on senior officials’ observations of Trump’s mental state.

If either of them — or any other senator — want eventually to challenge Trump in 2020, they are going to have to be bold, right now. Interestingly, Sasse is introducing legislation picking up on an idea from Sen. Elizabeth Warren (D-Mass.), a legal requirement for presidents to release their tax records. More will be needed, and on items that really matter.

Senators could, for example, demand that Supreme Court nominee Brett M. Kavanaugh recuse himself from Russia-related matters before they vote to confirm him. They could finally vote in favor of an independent commission to examine Russian interference in our elections and make recommendations (as the 9/11 commission did); demand the translator’s notes from Trump’s one-on-one meeting with Russian President Vladimir Putin in Helsinki; or take up other measures they should have pursued long ago as part of their oversight responsibilities. (Why did no Republican senator demand that Scott Pruitt resign as administrator of the Environmental Protection Agency?)

The big challenges for all these Republicans await — if Trump starts to pardon cohorts, refuses to sit down with the special counsel for an interview, or conducts his own Saturday Night Massacre. If they fail to defend the rule of law and our democracy at these critical junctures, they will have no business later mounting a primary challenge. And when Mueller’s report is finished, what will they do then? If they aren’t willing to demand impeachment and/or resignation based on replete evidence of obstruction (or ongoing lying to the American people about Trump’s Russia involvement), they should forget about running to replace Trump.

In 2020, if Republicans — or some portion of Republicans — want to break with Trump, they are going to look at what Republicans did, not how cleverly they ducked hard questions or managed to avoid infuriating the president. Meekness in the Trump era should be a disqualifier for 2020 primary contenders.

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